The present invention relates to a nonvolatile memory card and particularly to a technique which may be effectively adapted to flexible application such as alteration and addition of standards of a multimedia card.
A multimedia card is widely known as one of external storage media of a personal computer and a multifunction terminal equipment or the like. This multimedia card is applicable to every kind of digital information pieces in the recording of a still video image of a digital video camera, data of a mobile phone and music data of mobile player.
This multimedia card can maintain its compatibility with the multimedia card standards specified by MMCA (MultiMedia Card Association) which is a standardization organization.
A multimedia card has been produced through expansion of the Internet and spread of mobile phones and therefore it is not a traditional product. Moreover, in some cases, the multimedia card standards do not specify the measure for operations such as unexpected violation for the standards by a host side.
The inventors of the present invention have discussed an event that a card selection signal (CS) is negated during execution of access based on a command issued from the host in the operation mode wherein the multimedia card selected with the card selection signal generated by the host accepts the command and then executes the process.
As the process in the multimedia card to be executed as explained above, it is thought that the data input and data output are masked and the processes within the multimedia card are continued so long as a clock signal is inputted.